From the amorphous multilayer thin films composed of PbTiO0₃ and PbZrO₃ formed by a plasma-enhanced metal-organic chemical vapor deposition method, we have prepared single-phase PZT thin films by interdiffusion through an appropriate thermal annealing process. The transformation to a single-phase PZT from the multilayer was initiated at around 450℃ and was almost completed at 550℃ under an annealing time of 1 h. Typically, when a fourfold layer of PbZrO₃/PbTiO₃/PbZrO₃/PbTi0₃ was constructed and sequentially annealed at 650℃ under ambient O₂ for 1 h, the resulting films showed characteristics of a perovskite-type PZT and a uniform distribution of each element along the depth of the film. The electrical properties of the prepared PZT thin film (Zr/Ti = 54/46, 180 nm) on a Pt-coated substrate were as follows: dielectric constant ε_(?) = 415, coercive field ε_(?)= 200 and -140 ㎸/㎝, and remanant polarization P_(?) = 12 (u)_C/㎠ at an applied voltage of 6 V.